Protein and Peptide Letters - Volume 15, Issue 1, 2008

A convenient solid phase synthesis of a Thrombin Receptor Glycopeptide Mimetic analogue namely, 1-OMethyl- 2-N-{1’-(argininocarbonyl)-4’-[(4’’-fluoro)-benzylamido]-cyclohexane}-glucosamine using Fmoc/tBu methodology and the 4-Methoxybenzhydryl bromide resin is described. The synthesized analogue was purified by Reverse Phase High Performance Liquid Chromatography (RP-HPLC) and was identified by Electro Read More

Glutathione S-transferase was purified from bovine erythrocytes and some kinetic and characteristic properties of the enzyme were investigated. The purification procedure was composed of preparation of homogenate and Glutathione- Agarose affinity chromatography. Thanks to the procedure, the enzyme was purified 6,800 fold with 97% yield and a specific activity of 136 EU/mg proteins. On sodium dodecyl sulfate p Read More

Development of new chemical nucleases is a matter of great interest because of their extensive use in biotechnology and as therapeutic agents. The ATCUN (amino terminal Cu(II) and Ni(II) binding) is a peptide motif that occurs naturally in the serum albumins. The similar peptide motif (GlyAibHis) having unnatural amino acid Aib (α- aminoisobutyric acid) was synthesized and its Cu(II) complex was characterized by ESI-M Read More

Cystatins are thiol proteinase inhibitors ubiquitously present in mammalian body. In brain, they prevent unwanted proteolysis and are involved in several neurodegenerative diseases. In the present study, it has been demonstrated that photoactivated riboflavin and H2O2 induced modifications of high molecular mass goat brain cystatin (HM-GBC) leads to its inactivation and degradation. It was found that the damage with both t Read More

CYP2C19 is an important member of the cytochrome P-450 enzyme superfamily and plays a significant role in the drug metabolism. In order to gain insights for developing personalized drugs, the structure-activity relationships of two SNPs, W120R and I331V, with the ligands of CEC, Fluvoxamine, Lescol and Ticlopidine were investigated through the structure-activity relationship approach. By means of a series of dock Read More

Coiled coils are important structural modules and domains of protein-protein interactions. Further, they provide the required framework to proteins, like kinesins, myosins and SNAREs, which are either structural or involved in transport of biomolecules. We provide an interactive webserver to measure the strength of interactions between two helices involved in coiled coils. Interactions are measured using non-bonded and elec Read More

Beta-propeller phytases (BPPs) are a special class of enzyme that are mainly isolated from Bacillus and are widely used in animal nutrition, human health and environmental protection. BPPs class exhibits both unique Ca2+- dependent catalytic property and highly strict substrate specificity for the calcium-phytate complex. This review describes the effect of Ca2+ on the catalytic activity, thermal stability, and structural conform Read More

During analysis of the proteome in the cerebrospinal fluid (CSF) of the Caucasian form of moyamoya disease (MMD), a novel post-translational modification of human transthyretin was observed. Two-dimensional electrophoresis and subsequent peptide sequencing with ESI-MS/MS were performed to discover the γ-carboxylation of the Glu-42 (Gla- 42).

Differences evident in the sequence alignment of human cathepsin-L with shrimp cathepsin-L and silicatein-α suggest the indirect involvement of the heavy to light chain loop (E286 to E289) in the function of these enzymes. Deletion of the loop and adjacent residues S290 to N293, decreased specific protease activity by 81% and 63%, respectively; complete substitution for the corresponding silicatein-α loop decreased activity Read More

The hypervariable D3 domain of Salmonella flagellin, composed of the 190-285 segment, is the major determinant of flagellar antigenicity. D3 was cloned and overexpressed in E. coli. Although previous studies concluded that D3 is stabilized by interactions with the D2 domain, our calorimetric experiments have revealed that isolated D3 has a stable tertiary structure which is highly resistant against proteolytic digestion. Repeate Read More

S-adenosylmethionine is a metabolite regulating many biological processes; S-adenosylmethionine effect on ubiquitin-proteasome system (UPS) has not been studied yet. We investigated S-adenosylmethionine effects on UPS activity both in vitro, by inhibitor screening assay, and in rat vascular smooth muscle cells, by Western Blot of proteasomal targets. We found that S-adenosylmethionine inhibited UPS activity.

MiRP1 (encoded by the KCNE2 gene) is one of a family of five single transmembrane domain voltage-gated potassium (Kv) channel ancillary subunits currently under intense scrutiny to establish their position in channel complexes and elucidate α subunit contact points, but its structure is unknown. MiRP1 mutations are associated with inherited and acquired cardiac arrhythmia. Here, synthetic peptides corresponding to hu Read More

The polyadenylation factor subunit “Factor Interacting with Poly(A) polymerase” (Fip1) is an important bridging subunit in the eukaryotic polyadenylation complex. To better understand the functioning of Fip1 in Arabidopsis, a random combinatorial screen for peptides that interact with a conserved plant-specific domain in the protein was conducted. A search of the Arabidopsis proteome using these Fip1-binding peptide Read More

Processing of DNA replication and repair intermediates is a critical aspect of genome stability maintenance. The coordinated action of RecQ-like helicases with structure-specific nucleases such as Flap Endonuclease 1 plays an important role in the processing of certain DNA structures associated with the replication fork, DNA repair, or telomeres. We will summarize our current understanding of how and in what context Read More

The interaction of calreticulin with amyloid beta (Aβ) was investigated using solid phase and solution binding assays. Calreticulin bound Aβ 1-42 in a time and concentration dependent fashion. The binding was optimal at pH 5 and was stimulated by Ca2+ and inhibited by Zn2+ at pH 7. Interaction took place through the hydrophobic C-terminus of Aβ 1- 42 and the polypeptide binding site of calreticulin. The results are discussed in t Read More

Nudix hydrolases catalyze the hydrolysis of nucleoside diphosphates linked to other moieties X, and contain the sequence motif or Nudix box, GX5EX7REUXEEXGU. The mechanisms of Nudix hydrolases are highly diverse in the position on the substrate. In this paper, we examined the sequences and structures of the MutT/Nudix superfamily. And two recent developed methods were employed for data analyses of the su Read More

mBanana is a novel monomeric red fluorescent protein mutant. It was cloned and expressed in Escherichia coli with 10 histidine residues at its N-terminal. After cleavage of the His tag by TEV protease, the mBanana was further purified and crystallized by the hanging-drop vapor-diffusion technique. The crystals can diffract to 2.0Å resolution and one set of completed data was collected. It showed that the orthorhombic mB Read More

AxCesD protein required for bacterial cellulose biosynthesis in Acetobacter xylinum was overexpressed in E. coli, purified and crystallized. Single crystals of SeMet-substituted AxCesD were obtained by the sitting-drop vapordiffusion method. The crystal belongs to the primitive trigonal space group P32, with unit-cell parameters a = b = 77.7 Å, and c = 213.9 Å. The asymmetric unit in the crystal was assumed to contain 8 prot Read More